Vectorcardiography for Optimization of Stimulation Intervals in Cardiac Resynchronization Therapy

Vectorcardiography for Optimization of Stimulation Intervals in Cardiac Resynchronization Therapy

Current optimization of atrioventricular (AV) and interventricular (VV) intervals in cardiac resynchronization therapy (CRT) is time consuming and subject to noise. We aimed to prove the principle that the best hemodynamic effect of CRT is achieved by cancelation of opposing electrical forces, detectable from the QRS morphology in the 3D vectorcardiogram (VCG). Different degrees of left (LV) an...

Optimization of pacing intervals in cardiac resynchronization therapy

In patients with heart failure, left ventricular systolic dysfunction and prolonged QRS complex, cardiac resynchronization therapy (CRT) is a treatment method aimed at restoration of myocardial depolarization synchronicity. However, the extent of clinical and echocardiographic improvement depends on anatomical relations in individual patients, on structural changes in the heart, on intrinsic el...

Vectorcardiography as a Tool for Easy Optimization of Cardiac Resynchronization Therapy in Canine LBBB Hearts

Vectorcardiography as a tool for easy optimization of cardiac resynchronization therapy in canine left bundle branch block hearts.

BACKGROUND In cardiac resynchronization therapy (CRT), optimization of left ventricular (LV) stimulation timing is often time consuming. We hypothesized that the QRS vector in the vectorcardiogram (VCG) reflects electric interventricular dyssynchrony, and that the QRS vector amplitude (VAQRS), halfway between that during left bundle branch block (LBBB) and LV pacing, reflects optimal resynchron...

Phrenic stimulation: a challenge for cardiac resynchronization therapy.

BACKGROUND Phrenic stimulation (PS) may hinder left ventricular (LV) pacing. We prospectively observed its prevalence in consecutive patients with cardiac resynchronization therapy (CRT) devices. METHODS AND RESULTS In the years 2003 to 2006, 197 patients received a CRT device. PS and LV threshold measurements were carried out at implantation and at 6-month follow-up. LV reverse remodeling wa...